Hi there. I purchased 128mb of 60ns ECC EDO 168-pin DIMM (compaq, two 64mb modules) quite cheap on ebay. On their own the memory works perfectly, as do the two sticks of 64mb 50ns sun memory i already own. When i mix the two however (this is in an ultra 5), the sun shows my total memory as only 192mb, and not 256. Is this a known problem? Have i done wrong in mixing the different speeds? I'm absolutely baffled as on their own (sun and compaq) the ram seems to work fine. I've noted one or two support sites warn against mixing 11-bit and 10-bit ram modules. Have i done this unknowingly? Would it produce the effects i've experienced?